Apparatus for Retrieving a Gravitationally Propelled Load Traveling on a Cable

ABSTRACT

In connection with a gravitationally propelled load carrying system that includes an elongated suspended cable having a load carrying trolley movably supported thereon, an empty trolley retriever assembly adapted to push the empty trolley upwardly on the cable to be in position to take on a load where the assembly includes a plurality of idler pulleys rotationally carried by a base member where each of the pulleys is disposed in rolling engagement with the upper side of the cable to movably support the retriever assembly on the cable at a position intermediate the trolley and the lower terminal end of the cable, a motor driven drive wheel disposed intermediate the idler pulleys that engages the lower side of the cable, and a remotely operable control electrically connected to the motor for operatively rotating the drive wheel and propelling the retriever.

The present invention relates to a remotely controlled motor drivenapparatus for retrieving a gravitationally propelled load carryingconveyance that travels on and is supported by a sloping cable.

BACKGROUND

The broad nature of the present invention is personified in the presentday popular zip line systems that embody a gravitationally propelledcable-supported trolley for transporting a rider from the top elevatedend of a cable to the bottom lower end of the cable. In connection witha zip line, the retrieving apparatus retrieves the trolley from thelower end of the cable by pushing it back to the top end of the zip linecable immediately upon its discharge of the rider.

Prior art methods and apparatus for retrieving a zip linepassenger-carrying trolley from the bottom end of the zip line cableback to the top end have involved towing the trolley back to the top endstation with a rope, cable or motorized device, the latter of which isdescribed in U.S. Pat. No. 9,579,678 to Ronald Chasteen. Such a towingdevice works well but is burdened with time constraints, especially withlong length zip lines having high volume traffic. When the passengertrolley reaches the bottom end of the zip line the towing retriever musttraverse the same line itself and then tow the trolley back to the highend of the line to position it for another trip down the line.

The primary object of the present invention is to have a trolleyretriever in position at the bottom of the line to begin pushing thetrolley back to the top of the line immediately on the disembarking ofthe passenger from the trolley. After retrieving the trolley to the topend of the line, the pushing retriever is returned to the bottom at ahigh speed while the next zip line passenger is being readied for thedecent.

SUMMARY OF THE INVENTION

The zip line system to which the present invention applies includesupper and lower supports for an elongated zip line cable on which agravitationally propelled passenger-carrying trolley travels from theupper to the lower end of the zip line. The trolley retriever of thepresent invention is positioned at the lower end of the zip line cablebetween the trolley and the lower support. The retriever is adapted totravel on the zip line cable propelled by a reversible remotelycontrolled motor that drives the retriever to push the trolley up thezip line cable and then propel the retriever back down the cable toposition it for retrieving a subsequent trolley. Preferably, theretriever includes a body having idler pulleys that support theretriever on the cable and includes one or more drive wheels thatcontact the underside of the cable and which are driven, throughappropriate linkage, by the remotely controlled reversible motor mountedwithin the housing.

While one embodiment of the invention is described herein as a retrieverfor a zip line trolley, the scope of the invention includes using theretriever on a suspended cable to drive any kind of cargo or load thatis also suspended on and movable on the same cable.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic side view of a zip line in which a passenger iscarried by a gravitationally propelled trolley having a seat hangingfrom a cable-engaging trolley from an upper station to a lower station.

FIG. 2 is an upper perspective view of the right side of the retrieverof the present invention.

FIG. 3 is a perspective rear end view of the left side of the retrieverof the present invention.

FIG. 4 is a front end view of the retriever.

FIG. 5 is a cross sectional left side view of the retriever taken alonglines 5-5 of FIG. 2.

FIG. 6 is a fragmentary top perspective view of the drive wheel, motorand associated gearing.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

FIG. 1 illustrates the zip line system 2 to which the present inventionmay be applied. The system comprises a zip line cable 5 supported at ahigh elevation end by a column or similar supporting structure 8 andsupported at a lower elevation end by a column or other supportstructure 10. A passenger carrying gravitationally propelled trolley 12rides on the cable. The pushing retriever 14 of the present invention ismovably supported on the cable 5 between the trolley 12 and the lowerelevation support 10. In operation, after the passenger disembarks fromthe trolley at the lower station, a remotely controlled drive motor inthe retriever 14 is activated and the retriever is propelled by thedriving motor to push the trolley back to the upper station through theuse of a pushing rod 15 having an end-forming bracket 17 which makescontact with a portion of the trolley. Once the trolley is in positionat the upper station the driving motor is reversed and the retriever isrepositioned, as it is shown in FIG. 1, waiting for the next trolley 12to arrive.

FIGS. 2 thru 6 illustrate the preferred mechanism of the retriever. Theoperable components of the retriever are carried by a rigid bodycomprising a flat plate 22 with elongated extensions 25 and 26 and witha centrally located rectangular cut out 27. The left side of the plate22 comprises a turned up plate edge 29 to serve as a mounting base. Thedistal end of the extension 26 is turned down to form a plate 33 formounting a front collision bumper 34 for protecting the retriever frominadvertent damaging contact with the trolley or other objects. Alsosecured to the plate extension 26 is an elongated rod 15 having a Yconfigured distal end comprising the rod and a bracket 17 for makingcontact with a portion of the passenger trolley 12 to push the trolleyback up the cable. The lateral side of the distal end of the extension26 is turned up and turned over to form a pulley guard member 31 with acable enclosing pin 32. A similar pulley guard structure 35 with cableenclosing pin 36 is formed at the distal end of the elongated extension25. The turned down distal end of the extension 25 forms a plate 37 formounting a rear collision bumper 38 to protect the read end of theretriever.

Projecting from the right side of the flat body plate 22 is a lateralextension 40 which carries an enclosure 42 that houses an electric drivemotor 50. The output shaft of the motor terminates in a pinion gear 53that meshes with a drive gear 55. The output shaft of the drive gear 55interacts with a transmission 57 whose output is connected to a coupler60 whose output shaft 61 is supported by a pillow block bearing 63 andwhich output shaft becomes the axle of the drive wheel having a tire 70.The upper portion of the drive wheel and tire 70 protrudes through therectangular cut out 27 so that its peripheral surface of the tire makestangential contact with the underside of the cable 5. To achieve maximumdriving contact between the tire 70 and the cable 5 the tire is filledwith foam. The pressure of the cable on the foam filled tire causes thetire surface to be depressed at the point of cable contact so that thecable runs through a trough in the tire surface.

A pair of idler pulleys 81 and 83 are disposed on either side of thedrive wheel and tire 70. Each of the pulleys contacts the top side ofthe cable 5 to apply a spring driven downward force on the cable 5 tocreate driving friction between the cable and the drive wheel and tire70. The central shaft of each of the idler pulleys is supported by arms86 that are rotatably mounted on studs 87 that are mounted on andprotruding from the turned up plate edge 29. Also carried by the studs87 are torsion springs 89 each of which has one end 91 fixed to theupturned edge 29 and the other end laying against a respectivesupporting arm 86 in order to bias the related idler pulley down againstthe cable 5.

A container 95 depending from the plate 22 carries traditionalelectronic components to receive from a remote location signals thatoperate the drive motor and control its speed in a traditional manner.

I claim:
 1. A zip line system comprising, an elongated zip line cablewith upper and lower terminal ends and top and bottom sides, means forsupporting the upper and lower ends of the cable, a trolley movablysupported on the cable, a trolley retriever assembly disposed on thecable intermediate the trolley and the lower support and having, meansfor reversibly driving the retriever assembly up and down the cable, anda pusher rod attached to the retriever assembly and adapted to engagethe trolley to push the trolley upwardly on the cable.
 2. The system ofclaim 1 where the trolley retriever assembly further comprises, a base,a plurality of idler pulleys rotationally carried by the base in rollingengagement with the top side of the cable to movably support theassembly on the cable.
 3. The system of claim 2 and further including,means for pressure biasing each of the idler pulleys downwardly againstthe cable.
 4. The system of claim 3 and further including, a shaft onwhich each of the idler pulleys is mounted, a pivotal arm carried by thebase and supporting the shaft, a spring interacting between the base andthe arm to pressure bias the respective idler pulley downwardly againstthe cable.
 5. The system of claim 4 where the means for reversiblydriving the assembly up and down the cable includes, a reversiblevariable speed electric motor carried by the base, means for reducingthe speed of the motor having an output drive shaft, a circular drivewheel attached to the output drive shaft and disposed to make contactbetween the periphery of the drive wheel and the underside of the cable.6. The system of claim 5 where the drive wheel includes an elastic foamfilled tire.
 7. A gravitationally propelled load carrying systemcomprising, an elongated suspended cable with upper and lower terminalends and upper and lower sides, means for supporting the upper and lowerterminal ends of the cable, a load carrying trolley movably supported onthe cable, an empty trolley retriever assembly having, means forengaging the empty trolley to push the trolley upwardly on the cable, abase member, a plurality of idler pulleys rotationally carried by thebase member where each of the pulleys is disposed in rolling engagementwith the upper side of the cable to movably support the retrieverassembly on the cable at a position intermediate the trolley and thelower support means, a rotatable drive wheel engaging the lower side ofthe cable and disposed intermediate the idler pulleys, means foroperatively rotating the drive wheel, and a remotely operable controlelectrically connected to the means for operatively rotating the drivewheel.
 8. The gravitationally propelled load carrying system of claim 7and including means for applying idler pulley biasing pressure againstthe cable to produce frictional engagement between the cable and thedrive wheel.
 9. A method for repositioning a load carrying trolley fromthe lower terminal end of an inclined carrying cable back to the upperend of the cable, comprising the steps of, positioning a motor drivenretriever at the bottom terminal end of the cable, releasing a gravitydriven load carrying trolley to travel down the cable and engage theretriever, activating the motor driven retriever to push the trolleyback up the cable, and returning the retriever to the bottom terminalend of the cable.
 9. The method of claim 8 where the step of returningthe retriever to the bottom terminal end includes the step of,activating the motor driven retriever to travel down the zip line cableat a speed greater than that which would be produced by gravitationalpull.